ABSTRACT: More than ninety jurisdictions have some form of merger control regime under their antitrust or competition laws. Numerous other jurisdictions lack a formal merger control mechanism, but reserve the right to review and challenge mergers under their general competition laws, sector-specific laws, or regional trade agreements. Observing the substantive approaches to merger analysis across jurisdictions, one sees many commonalities, but also some important areas of variation. The procedural approaches across merger control regimes are even more varied.

This chapter seeks to identify and catalog the key substantive and procedural norms and differences in various systems, to provide a sense of the direction of the academic scholarship on various issues and to offer some analytical underpinnings for optimal merger enforcement based on the reality of merger control in recent years. We conclude with suggestions regarding the future direction of merger control.